Cleaning up JDK detection in IcedTea

[Matthew Flaschen]

Andrew John Hughes wrote:
> This patch:
> 
> * merges all the --with-gcj-jdk, --with-icedtea-home,
> --with-openjdk-home options into one option: --with-jdk-home is now
> the one and only option for specifying the JDK to use.
> * makes more use of the JDK setting in deciding which javac, java,
> jar, rmic and javah to use.
> * removes --with-icedtea and --with-openjdk, replacing them with the
> more accurate --disable-bootstrap

This looks very useful.  Fewer options with the same functionality means
less ways to screw up the configuration.

Matt Flaschen